The present invention concerns a resilient leg as part of an attachment for the wheel of a vehicle.
The overall design of such a resilient leg is generally known. A piston rod travels into and out of a housing. The inner end of the piston rod is provided with a shock-absorbing piston. The piston itself can be provided with channels and valves to establish a prescribed shock-absorption performance curve.
Resilient legs are attached, preferably at one end, to the vehicle""s chassis. They are generally but not necessarily provided with a resilient disk to accommodate the base of a helical spring. The bottom of the leg is provided with a flange. Both the wheel bearing components and the wheel-turning rods are attached to the flange.
Since the wheel is attached remote from the leg""s midline, the leg will need to transmit moments that express themselves as radial forces exerted on both the piston and the piston rod""s upper guide. Attempts have of course been made to compensate for moments introduced by the wheel by tilting the disk and modifying the spring. This approach, however, is inadequate because the force of the moment varies with the vertical distance of the wheel from the chassis.
One attempt to compensate for these moments and their accompanying horizontal forces is illustrated in Figure 6.43, Reimpell-Stoll, Fahrwerktechnik: Stoss- und Schwingungsdxc3xa4mpfer, 1989. Here, the piston rod is radially supported by two separated bearings. This approach, however, is very complicated and is to some extent applicable only to light-weight legs.
The object of the present invention is accordingly to improve the generic resilient leg to the extent that moments of force will be reliably transmitted from the piston rod to the housing. Such a leg can be light in weight.
A resilient leg in accordance with the present invention has several advantages. First, moments of force exerted on the leg can be transmitted from the piston rod to the housing in accordance with the least possible radial forces. Second, the piston-rod alignment and sealing components will be subject to little friction, facilitating the rod""s travel into and out of the housing. Finally, since the piston rod will need to transmit only slight angular moments, it can be thinner and hence lighter in weight.